2 PHILOSOPHICAL TRANSACTIONS. [aNNO 1735. 



not differ 1 minutes; 181 that do not differ 3 minutes ; and 214 that do not 

 differ 4 minutes ; the rest not differing above 5\ minutes. 



Experiments and Observations on the Light, produced by communicating Electri- 

 cal Attraction to animate or inanimate Bodies; ivith some of its most surprising 

 Effects. By Mr. Stephen Gray. N° 436, p. l6. 



The several new electrical discoveries made by M. Dufay, especially that im- 

 portant luciferous one, mentioned in a former Transaction, led Mr. Gray to 

 make the following experiments : — 



He began first with some common utensils that were at hand, as the iron 

 poker, tongs and fire-shovel ; any of these being suspended on lines of the 

 largest sewing silk, and then the excited tube being applied first to the knob of 

 the poker, and afterwards to the hand, the snap and pricking were felt ; and 

 the effect was the same, when the tube was first applied to the other end of the 

 poker. He had by him a three-pronged iron instrument, made many years be- 

 fore ; being designed for propping up the observatory table, when he observed 

 the spots in the sun. The prongs were about 4- an inch in diameter, two of 

 them about 22 inches, and the third about 8 inches long, and pointed. This 

 being laid either on cylinders of glass, or cakes of rosin and bees-wax, or on a 

 cake of sulphur, the tube being applied to the end of any of the legs, while 

 the hand or cheek was applied near the other, both the other legs had the same 

 effect, as that to which the tube had been applied ; but by holding his cheek 

 near any of the points of the legs, the pricking or burning pain was much 

 more sensibly felt, and even sometimes for several minutes after. 



As to the success in repeating M. Dufay's experiment at Mr. Wiieeler's, 

 they procured silk lines strong enough to bear the weight of his foot-boy, a 

 good stout lad : then having suspended him on the lines, the tube being applied 

 to his feet or hands, and the finger of any one that stood by held near his 

 hands or face, he found himself pricked or burnt, as it were, by a spark of fire, 

 and the snapping noise was heard at the same time: but it did not succeed when 

 they applied their hands to any part of his body through his clothes, except 

 upon his legs, where he felt the pain through his stockings, though they were 

 very thick ones. 



They took also a large white cock, and suspending him on the lines, first 

 alive, the effect was the same as on the boy, whether they applied their fingers 

 to any part of his body, or their cheek to his beak, or comb or claws. The 

 cock was then killed, and put on the lines again ; when they found very little, 

 if any difference, from the effect it had when the cock was living. They then 



